Dear Atheist friend,
Your demand for proof raises a problem. “Proof” is not a part of your worldview, and asking for it undermines your argument.
Honest atheism does not admit the existence of any absolute standard, any true point of reference. Everything is governed by chaos; the universe is only stardust randomly bumping into stardust. Within a consistent, atheistic paradigm nothing could ever be truly known or proven.
The idea of “proof” belongs to the worldview of those who believe in a Supreme Creator who has put order, logic, consistency, and structure into the universe. A believer in a wise, all knowing Creator can think in terms of “proof” and “evidence,” but not a person who sees the universe as a random collision of particles.
Your request presupposes something you don’t believe in. It borrows from the worldview you are trying to deny.
Your statement self-destructs.